To determine the unknown compound based on the flame color observed in the photo, we will match the described flame color with the known metal flame colors.
Here's a reference for flame colors:
- Barium: light green
- Calcium: brick red
- Copper: blue/green
- Lead: blue/white
- Potassium: lilac
From your description, the prominent flame color is "bright red but like an orange color". This aligns most closely with the flame color of **calcium**, which is known for producing a brick red flame.
Considering other details, such as the mention of a light blue area, it suggests that there might be some mixture with other compounds, but the primary observation that stands out is the bright red/orange color, which predominantly suggests the presence of calcium.
Hence, the unknown compound is likely:
**B. Calcium chloride**